M21 transmition 660 case vs 661

[P.J.]

I received this email re the M21 660 case and the 661 case.
HEY PETER, I PERSONALLY HAVEN'T SEEN A 660 M20 OR M21 THAT HAD A DRAIN PLUG. M22'S ARE THE ONLY 660 CASE I HAVE SEEN WITH THE PLUG. THAT'S NOT TO SAY THEY DON'T EXIST!! THE M21 I HAVE DON'T HAVE THE PREFIX B THAT DENOTES ITS A M21 EITHER BUT IT IS. I THINK THEIR ARE A LOT OF LITTLE THINGS THAT SOME TRANNYS HAVE THAT ARE FACTORY BUT NOT REALLY MENTIONED AS A GIVEN RULE. ALL 661 CASES HAVE A DRAIN PLUG NO MATTER IF ITS A M20 21 OR 22 OR NOT. ----- Original Message -----